Touch-activated or -interactive devices, such as screen surfaces (e.g., surfaces of electronic devices having user-interactive capabilities that are activated by touching specific portions of the surfaces), have become increasingly more prevalent. In general, these surfaces should exhibit high optical transmission, low haze, and high durability, among other features. As the extent to which the touch screen-based interactions between a user and a device increases, so too does the likelihood of fingerprint residue adversely affecting the touch screen surface.
Fingerprint residue, which can include not only natural fingerprint- or fingerborne-oils or grease, but also dirt, cosmetics, hand creams/lotions, or the like coupled therewith, can render a touch screen (or any other aesthetic or functional) surface unsightly and/or less user-friendly or functional. Further, an accumulation of such residue can lead to a distortion in the transmission and haze properties of the touch screen surface. That is, as a user contacts and operates the touch screen surface, fingerprint residue is transferred to the surface. When a fingerprint residue-rich region of the surface is subsequently manipulated, the fingerprint residue can smudge or smear across the surface. These smudges and smear marks are visible to the naked eye, and can affect how an image from the touch screen surface is observed by a user. With significant build-up, in some cases, these smudges and smear marks can interfere with the function of a device by obscuring objects that must be seen for use and/or transmission of information into or from the device.
To combat the deleterious effects of fingerprint residue transfer (or other undesirable residue transfer), numerous so-called “anti-fingerprint” or “fingerprint-resistant” technologies have been developed. These technologies generally involve making a modification to the touch screen surface and/or applying a coating or film to the touch screen surface to render the surface both hydrophobic and oleophobic. The aim of such approaches is towards preventing the transfer of fingerprint residue in the first place, while also enabling easy removal of any residue that ultimately is transferred. Unfortunately, while these technologies may improve the fingerprint “soiling” resistance of some touch screen or other surfaces, the improvements generally are at the expense of other features. For example, certain hydrophobic and oleophobic coating materials can cause a decrease in transmission, an increase in haze, and/or a decrease in scratch resistance relative to the uncoated touch screen surface.
Rather than focus on preventing fingerprint residue transfer as with anti-fingerprint technologies, a few alternative technologies have sought “anti-smudge” or “smudge-resistant” features, wherein the aim is towards enabling, or even promoting, fingerprint residue transfer. The transferred fingerprint residue can become hidden to the naked eye because it wets or coats the surface, instead of smudging or smearing, but can also be removed in a relatively easy fashion (e.g., by wiping with a cloth). Just as with anti-fingerprint technologies, however, existing smudge-resistant technologies are often accompanied by sacrifices in other desirable features (e.g., transmission, haze, strength, scratch resistance, and the like).
There accordingly remains a need for technologies that provide touch screen and other aesthetic or functional surfaces with improved resistance against the adverse effects of fingerprint or other undesirable residue. It would be particularly advantageous if such technologies did not adversely affect other desirable properties of the surfaces (e.g., transmission, haze, strength, scratch resistance, and the like). It is to the provision of such technologies that the present disclosure is directed.